Project Summary/Abstract Population demographic trends suggest an expected dramatic increase in age-associated dementias and a looming public health crisis. Current emphasis is on disease prevention, with a focus on older adults who express early cognitive impairment. The SMART (Statistical Modeling of Aging and Risk of Transitions) has successfully harmonized data from nine different longitudinal studies on aging involving records on 5,032 subjects, with 1,657 having autopsy information. We propose to identify authoritatively the roles of diabetes and hypertension on the occurrence and duration of pre-dementia states, as well as mixed pathology. The project has shown that self-reported diabetes is not a risk for Alzheimer pathology but is a risk for cerebrovascular pathology, that subjective memory complaints are a risk for a future cognitive impairment, and that transitioning to a subjective complaint or even to mild cognitive impairment is no guarantee of future dementia. The SMART renewal proposes to obtain Medicare claims data on its participants to determine the severity of diabetes, hypertension and other comorbidities that have not been investigated, such as renal disease, with a focus on improving the prediction of who is at risk for a transition to an impaired cognitive state and mixed dementia pathology. This will be accomplished through the following specific aims: Aim 1. Update and extensively revise the existing SMART project database with additional participant data; obtain and integrate linked Medicare claims data; assess agreement between self-reported medical history and claims data. Aim 2. Investigate the relationship of HTN, T2DM, and multimorbidity in advanced old age with AD and non-AD neuropathologies. Aim 3. Investigate the relationship of HTN, T2DM, and multimorbidity in advanced old age with cognitive states including subjective memory complaints, mild cognitive impairment, and dementia.